🔍 Key Concepts

• Vacuum tube transmitter components – filament (heater), plate, and gas inside the envelope • How a filament failure affects tube operation and visible indications • Relationship between tube condition and transmitter output power

💭 Think About

• For each choice, ask: Would this condition reasonably happen when a vacuum tube is defective, and would it be visible or measurable? • Think about what you would see when looking at the tube, and what you would measure on the transmitter output meter if the tube is bad. • Consider whether a single defect in a tube can cause more than one symptom at the same time.

✅ Before You Answer

• For each option, decide if it is plausible as a symptom of tube failure based on basic electronics: loss of heat/light, abnormal glow, or lower power. • Ask yourself whether reduced RF output is a common sign of any defective active component in a transmitter. • Before picking an answer, check if more than one option can be true at the same time; if so, consider whether a combined option fits best.